There are 2 main reasons for the soreness of the muscles on the right side of the waist: 1. As the muscles on the right side of the waist are in a state of tension, overwork and strain, it leads to the production of very large amounts of inflammatory metabolites and other metabolites such as lactic acid in the muscle tissue. The increase in the accumulation of metabolites will stimulate the peripheral nerves around the inflammatory metabolites stimulation will lead to local pain symptoms, lactic acid stimulation of peripheral nerves will lead to local symptoms related to acidity. 2, due to cold in the lumbar region, because once the lumbar region is cold it will lead to muscle tissue becomes more tense, blood circulation will also decline. Muscles are more likely to produce more metabolites accumulation, after the venous return is reduced will lead to increasing metabolites, there may be inflammatory edema. In addition, after the arterial blood supply decreases, the local electrolyte energy will also decrease accordingly, which will lead to the symptoms of soreness and pain in the lower back becoming more pronounced. Therefore, it is important to keep the muscles of the lower back relaxed and warm after this condition occurs.